JPH11303846A - Propeller shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a propeller shaft which can obtain a stable shock absorbing characteristic at a low cost and increase the safety at the collision time, without blocking the deformation amount of a car body at the collision time. SOLUTION: The other end 1b side of a yoke member 1 with whose one end 1a side a drive source or driven member is connected is inserted by a spline at one side of a sleeve 2 and also the tip 3 of the other end 1b of the yoke member 1 is calked by the extension part, 2b extended in the direction same as the yoke member insertion direction provided on the other side of this sleeve 2 so as to hold the other end 1b side od the yoke member 1. A hollow shaft 4 is installed to the sleeve part 2 so that this calked part G is positioned to the inside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a propeller shaft having a shock absorbing function.

[0002]

2. Description of the Related Art In the field of automobiles, a cabin is provided with strength, and an engine room and a trunk room located before and after the cabin have a lower strength than the cabin to form a so-called crushable zone. A variety of crushable bodies have been proposed that employ a crushable body for protecting the occupant by reducing the impact on the occupant at the time.
Such a crushable body fulfills its function by crushing the crushable zone as designed. In recent years, the presence of a propeller shaft has been cited as an obstacle to the crushable zone being crushed.

[0003] Propeller shafts include a single type or a split type in which a plurality of shafts are connected by various connecting members such as a universal joint according to the type of automobile. These connect a transmission to a driven member such as a differential gear, and transmit rotational torque generated by a drive source such as an engine from the differential gear to wheels. In particular, those used for FR vehicles and 4WD vehicles have a propeller shaft extending in the front-rear direction of the vehicle body, so that the propeller shaft is stretched at the time of collision from the front-rear direction of the vehicle body. For this reason, at the time of collision, movement of the engine, differential gear, and the like is restricted, and the crushable zone is prevented from being crushed even if an impact load is applied from the front-rear direction of the vehicle body. The impact load that has been reduced by the tension may temporarily increase, and the impact on the occupant may not be absorbed. Also, when the propeller shaft is a divided type in which a plurality of shafts are connected, the propeller shaft may bend due to an impact load applied to the propeller shaft, and may interfere with the fuel tank or protrude into the cabin depending on the bending position and direction. Is concerned.

In order to solve such a problem,
Japanese Unexamined Patent Publication No. Hei 7-119728 discloses that a yoke member constituting a universal joint is provided at one end of each of two shafts so that both can be slid and contracted at the other end of each shaft. A C-ring is mounted on one of the outer peripheries to regulate the mutual movement of the shaft when the load is less than a predetermined axial load. If a predetermined impact load is applied due to a collision from the front and rear of the vehicle, the C-ring is restricted. A structure has been proposed in which the propeller shaft is moved in the axial direction due to loss (breakage).

[0005]

SUMMARY OF THE INVENTION
In the structure of the propeller shaft described in JP-A-119728, the C-ring is provided at a position that is separated from the tip of the shaft and regulates the position of each shaft in the contraction direction, so that an impact load is applied to the propeller shaft. When each axis moves in the contraction direction, depending on the position of each axis,
Variations occur in the load applied to the C-ring depending on the distance traveled until it comes into contact with the ring. For this reason, when trying to reduce the impact load applied to the propeller shaft by breaking the C-ring, there is a problem that it is difficult to adjust the impact load characteristics. In general, the C-ring has a large shearing force and is not easily broken, which also makes it difficult to adjust the shock absorption characteristics by the C-ring.

SUMMARY OF THE INVENTION An object of the present invention is to provide a propeller shaft capable of obtaining stable shock absorbing characteristics at low cost without hindering the amount of deformation of a vehicle body at the time of a collision and improving safety at the time of a collision. .

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a yoke member having a driving source or a driven member connected to one end thereof and one yoke member being connected to the other end of the yoke member. Along with the spline fitting, the other end has an extension extending in the same direction as the yoke member insertion direction, and the other end of the yoke member is held by caulking the other end of the yoke member with the extension. The yoke member has a stable position because it has a sleeve portion to be formed and a hollow shaft portion mounted on the sleeve portion so that the caulking portion is located inside. When an impact load is input to one end of this stable yoke at the time of a collision, the impact load is transmitted through the caulked portion of the yoke member, and when the impact load exceeds the holding force of the caulked portion of the extension portion, the yoke member is moved. Sliding in the load direction while plastically deforming the swaged part eliminates the propeller shaft tension.

According to the second aspect of the present invention, since the sleeve portions are provided at both ends of the hollow shaft portion located in the input / output direction, even if an impact load applied to the propeller shaft is input from any direction in the input / output direction of the hollow shaft, the impact portion is not impacted. The load can be effectively absorbed and alleviated. Examples of the tip on the other end side of the yoke member that is swaged by the extension portion include an end on the other end of the yoke member and an intermediate member that is in contact with the tip on the other end of the yoke member. When the intermediate member is interposed, when the impact load exceeds the holding force of the caulked portion of the extension portion, the yoke member slides in the load direction while plastically deforming the caulked portion by the intermediate member, eliminating the propeller shaft tension In addition, individual materials can be selected for the material of the yoke member and the intermediate member, and the length of the yoke member can be shortened, so that the manufacturing and workability of the yoke member can be improved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. The propeller shaft shown in FIG. 2 connects a transmission 12 and a differential gear 13 serving as a driven member, and transmits rotational torque generated by an engine serving as a driving source (not shown) from the differential gear 13 to driving wheels (not shown). The propeller shaft has crushable zones in the front-rear direction (hereinafter referred to as “front-rear direction A”) of the vehicle body in the input / output direction indicated by arrow A, and includes a high-strength cabin between the crushable zones. It is applied to vehicles having a well-known crushable body.

The propeller shaft has a steel pipe 4 serving as a hollow shaft disposed at the center thereof and slide yokes 1 and 1 serving as yoke members at both ends 4a and 4b located in the front-rear direction A.
And sleeves 2 and 2 serving as sleeve portions. One end 1a of the slide yoke 1 on one end 4a side is
Front and rear direction A by spline connection to transmission 12
The output shaft 14 is slidably supported on the output shaft 14, and is connected via a universal joint 16 and a connection yoke 15. One end 1a of the slide yoke 1 on the other end 4b side is connected to the differential gear 13 via a universal joint 18 and a connection yoke 17. Each slide yoke 1,1 is connected to a universal joint 16,1.
8 and the connecting yokes 15 and 17 each constitute a universal joint. The configurations of the sleeves 2 and 2 are basically the same, and are arranged symmetrically around the steel pipe 4. Therefore, the configuration of the sleeve 2 on the one end 4a side will be described in detail below as a representative.

As shown in FIG. 1, the slide yoke 1
One end 1a serving as a mounting portion for the universal joint 16 is provided.
b is formed of metal with a hollow shaft portion, and the other end 1b
A spline tooth portion 1e extending in the axial direction is formed on the outer peripheral surface of. A circumferential groove 9 is formed on the outer peripheral surface of the other end 1b located near the end surface 1c of the slide yoke 1,
A snap ring 8 described later is fitted.

The sleeve 2 has a cylindrical shape as a whole and is formed by cold forging with metal, so that the other end 1b of the slide yoke 1 can be inserted therethrough. Inner peripheral surface 2d of sleeve 2
A spline tooth portion 2e engaging with the spline tooth portion 1e is formed near the end face 2a of the spline tooth portion 1e.
e and 2e are press-fitted and fitted to each other to hold the slide yoke 1 inside. For this reason, the sleeve 2 is supported by the spline fitting portion 10 so as to rotate integrally with the slide yoke 1 and relatively move in the axial direction. The spline teeth 1e and 2e are aligned with each other with a large diameter.
These are press-fitted and fitted to form a spline fitting portion 1.
Zero play is achieved, and the rotational balance of the propeller shaft is stabilized.

A step 2f is formed on the inner peripheral surface 2d of the sleeve 2 at a boundary between the spline teeth 2e. The snap ring 8 inserted into the circumferential groove 9 is formed to have a size that comes into contact with the step 2f. When the snap ring 8 comes into contact with the step 2f, the projecting position of the slide yoke 1 from the end surface 2a of the sleeve 2 is formed. Has been established. The movement amount S of the slide yoke 1 is from the contact surface 1d formed behind the one end 1a to the end surface 2a. Thus, by providing the snap ring 8 and keeping the position of the slide yoke 1 and the moving amount S constant, the rotational balance of the propeller shaft is stabilized. The snap ring 8 functions to prevent the slide yoke 1 from coming off from the sleeve 2 when the transmission 12 and the output shaft 14 move due to a stroke displacement of a suspension (not shown), and to provide the sleeve 2 with the seat 3.
It has a retaining function when caulking.

A steel pipe 4 is provided on the outer peripheral surface at substantially the center of the sleeve 2.
Is formed with a step peripheral portion 2b into which one end 4a is inserted.
The sleeve 2 is fixed to the steel pipe 4 by welding the vicinity of the step peripheral portion 2b in the circumferential direction in a state where the step peripheral portion 2b is inserted into the tip 4a. Reference numeral 11 indicates a welded portion.

As shown in FIG. 3, an extension 2c is formed on the step peripheral portion 2b so as to extend in the extension direction of the other end 1b, which is the insertion direction of the slide yoke 1. This extension 2c
In this embodiment, it is formed in a circumferential shape thinner than the step peripheral portion 2b. It should be noted that slits may be formed at appropriate intervals on the circumference of the extension 2c and divided. Extension 2c
Is arranged in the inside 4c of the steel pipe 4, as shown in FIG.
When they are bent inside the sleeve 2, they are provided with lengths that do not overlap each other. The total length from the end surface 2a of the sleeve 2 to the tip of the extension 2c is shorter than the length from the contact surface 1d of the slide yoke 1 to the end surface 1c. A sealant is applied to the end surface 2a of the sleeve 2 to prevent dust, water, and the like from entering the sleeve 2, so that appropriate sealing properties and rust prevention are ensured.

In the sleeve 2, a seat 3 is disposed as an intermediate member such that the one end surface 3a of the seat 3 abuts against the inner end surface 1c of the slide yoke 1. The sheet 3 is formed in a ring shape by cold forging, and has an outer diameter substantially equal to that of the sleeve 2.
Is formed to have the same diameter as the inner peripheral surface, and the outer peripheral surface 3a is slidably contacted with the inner peripheral surface 2d. As shown in FIG. 1, the seat 3 has such a thickness that the other end face 3b is located near the extension 2c when the slide yoke 1 inserted into the sleeve 2 is protruded from the sleeve 2 to the maximum. Have. The sheet 3 is sandwiched between the end face 1c and the extension part 2c of the slide yoke 1 by bending the extension part 2c inward and caulking the bent part, and the end face 1c and the extension part 2c.
c are held in the sleeve 2 in a state where both end surfaces 3a and 3b are in contact with each other, and are substantially covered with the front surface. The symbol G in the figure indicates a caulking portion. That is, the steel pipe 4 is mounted on the sleeve 4 so that the swaged portion G is located inside. The sheet 3 is made of carbon steel. As a processing method of the sheet 3, a desired shape can be formed at low cost by using a cutting process instead of the cold forging.

The procedure for assembling the propeller shaft will be described with reference to FIG. As shown in FIG. 4 (a), the end face 1c of the slide yoke 1 in which the spline teeth 1e and the circumferential groove 9 are formed in advance, and the tooth faces of the sleeve 2 in which the spline teeth 2e are formed in advance are attached to each other. The sleeve 2 is mounted on the slide yoke 1 by abutting the two so as to engage with each other and lightly press-fitting the two. The slide yoke 1 and the sleeve 2 are relatively slid in the axial direction until the circumferential groove 9 projects outside the extension 2c, and the snap ring 8 is mounted.

Next, as shown in FIG. 4 (b), the sleeve 2 and the slide yoke 1 are relatively moved in such a direction that the distance between them increases, until the snap ring 8 contacts the step 2f of the sleeve 2. Further, the seat 3 is inserted into the sleeve 2 from the extension 2c along the inner peripheral surface 2d, and the one end surface 3
Push in until a contacts the end face 1c.

As shown in FIG. 4C, after securing the contact state between the sheet 3 and the end surface 1c, each extension 2c of the sleeve 2 is bent inward at a substantially right angle to the other end 3b of the sheet 3. , Each bent portion is crimped in the circumferential direction, and the sheet 3 is held between the end face 1c and the bent extension portion 2c. Then, in order to attach the sleeve 2 assembled in this way to the steel pipe 4, the step peripheral portion 2 b is attached to the steel pipe 4.
The crimping portion G and the sheet 3 are arranged in the inside 4c of the steel pipe 4 by inserting the two insertion portions indicated by the arrow D from the outside in the circumferential direction and fixing them.

The heat generated when the sleeve 2 and the steel pipe 4 are welded may cause thermal deformation of the spline fitting portion 10 between the sleeve 2 and the slide yoke 1. However, in this embodiment, since the sheet 3 is in contact with the end face 1c and the extension 2c, the heat at the time of welding is also transmitted to the sheet 3 and the heat applied to the spline fitting portion 10 is reduced, and the spline fitting is performed. Part 10
Is prevented from being thermally deformed. For this reason, when the impact load F is applied to the slide yoke 1, the resistance due to the thermal deformation of the spline fitting portion 10 is eliminated, and the movement of the slide yoke 1 is not overloaded due to the thermal deformation. This means
The load fluctuation for moving the slide yoke 1 is suppressed, and the slide yoke 1 can be stably moved.

The operation of the propeller shaft configured as described above will be described. In FIG. 1, when an impact load F is applied from a front direction indicated by an arrow B, a crushable zone such as an engine room formed on a front side of a vehicle body (not shown) is deformed in an initial stage of a collision and the impact load F is absorbed. When the deformed portion collides with the engine, the impact load F is transmitted from the transmission 12 to the slide yoke 1.
Is transmitted to Impact load F applied to slide yoke 1
However, when the value exceeds the first resistance of the spline fitting portion 10 and the second resistance of the caulking portion G, the slide yoke 1 moves in the contraction direction. When the slide yoke 1 moves,
The first resistance caused by the spline fitting portion 10 increases with the movement of the slide yoke 1, and the bent extension portion 2c is pushed by the sheet 3 so that the extension portion 2c is caulked.
And the second resistance increases due to plastic deformation in the direction of opening from the opening. That is, the impact load F applied to the propeller shaft is absorbed by the resistance of the spline fitting portion 10 and the energy for plastically deforming the caulked portion G. The movement of the slide yoke 1 stops when the contact surface 1d contacts the end surface 2a of the sleeve 2.

The strength of the caulked portion G with respect to the impact load F is
When the impact load F is input, the impact is set so that a reference impact, which is a fatal impact on a passenger in a cabin (not shown), is not generated. If the strength of the caulked portion G with respect to the impact load F is set so as not to exceed the reference impact, even if the impact load F is applied to the slide yoke 1, an excessive impact load due to the stepping of the caulked portion G can be obtained. The rise can be suppressed. At the same time, the impact load F can be sufficiently reduced by the force for plastically deforming the caulked portion G and the resistance of the spline fitting portion 10. Therefore, the ratio of the stroke amount S of the slide yoke 1 to the absorption rate of the impact load F can be reduced,
The stroke amount S of the slide yoke 1 can be reduced. Therefore, the spline fitting portion 10 can be shortened, and the weight and manufacturing cost of the propeller shaft can be reduced. Thereby, the propeller shaft is reliably contracted by the sleeve 2 as shown in FIG. If the impact load F cannot be completely absorbed by the sleeve 2, if the contact surface 1d is
By contacting a, the sleeve 2 mounted on the other end 4b side via the steel pipe 4 acts, so that the impact load F is further absorbed and alleviated.

When a collision load F is applied to the vehicle body from the rear as indicated by an arrow C in FIG. 5B, the collision load F is transmitted to the sleeve 2 via the differential gear 13,
As shown in FIG. 5 (c), when a collision load F is applied to the vehicle body from the front direction B and the rear direction C, the collision loads are transmitted to the sleeves 2 and 2, respectively. By the action of 2, the effect of absorbing and relaxing the impact load can be obtained.

Since the propeller shaft is stretched in this way, the crushable zone set in the vehicle body can be sufficiently deformed, and the impact load F can be reliably reduced at the initial stage of the collision. In addition, the collision load F applied to each slide yoke 1 without being completely absorbed in the crushable zone increases as the movement of the slide yoke 1 in the contraction direction progresses due to the plastic deformation of each spline fitting portion 10 and the caulking portion G. Absorption will be mitigated. In other words, the shock absorbing performance of the propeller shaft is improved while the shock absorbing performance inherent in the vehicle body is reliably exhibited, and the impact on the occupant of the cabin is minimized, thereby improving safety.

The caulked portion G is arranged in the inside 4c of the steel pipe 4, and the slide yoke 1 is also arranged in the inside 4c via the sleeve 2. Therefore, the slide yoke 1 to which the collision load F is applied is Slides in the inside 4c of the propeller shaft, and the bend of the propeller shaft is eliminated. For this reason, it is possible to prevent the propeller shaft from projecting into the cabin (not shown) due to bending and interference with the fuel tank, thereby further enhancing the safety of the vehicle.

The spline fitting portion 1 in the present embodiment
Reference numeral 0 denotes a configuration in which a linear tooth portion extending in the axial direction is formed in the circumferential direction on the slide yoke 1 and the sleeve 2, but one of the slide yoke 1 and the sleeve 2 has an inclination angle (in the rotation direction of the slide yoke 1). (Lead) may be formed. When the spline fitting portion is configured in this manner, play in the rotation direction can be further reduced, and
When the impact load F is applied to the slide yoke 1 and the slide yoke 1 moves, the resistance of the spline fitting portion increases, and the shock absorption rate of the fitting portion can be increased. Also in this case, the resistance of the spline fitting portion is set in a range in which the impact on the occupant of the cabin (not shown) is lower than the reference impact, as in the case described above.

In the present embodiment, the sheet 3 is placed in contact with the end surface 1c of the slide yoke 1 in consideration of the thermal deformation of the spline fitting portion 10 due to the heat at the time of welding. Was held by the extension 2c of
If the position of the welded portion 11 is set at a position away from the spline fitting portion 10 or if there is no possibility that thermal deformation has almost any influence on the movement of the slide yoke 1, the slide yoke 1 is formed to extend beyond the present embodiment, Of course, the edge portion 1f (see FIG. 1) near the end surface 1c serving as the tip may be directly caulked by the extension portion 2c.

The sleeves 2 and 2 are connected to both ends 4 of the steel pipe 4 respectively.
a and 4b are provided, but the present invention is not limited to this. At least one of them is only required to be mounted, and in FR vehicles and 4WD vehicles, it is preferable to arrange them at least on the front side. I can. That is, if the amount of movement of the slide yoke 1 that can at least appropriately deform the crushable zone can be ensured at either the front end 4a or the rear end 4b of the steel pipe 4, the configuration of the present invention will It may be provided at either the front end 4a or the rear end 4b. In the figure, the propeller shaft is described as a single undivided one, but the above-described sleeves 2, 2 are used.
It is of course possible to adopt a split type propeller shaft. Even in this case, the number of the sleeves 2 may be one as long as the impact absorption characteristic for securing the appropriate deformation amount in the vehicle body can be secured at one place.

In the embodiment, the extension 2c of the sleeve 2
The impact load F is absorbed and relaxed by the loose deformation of the caulked portion G. Therefore, by changing the strength at which the extension 2c is crimped and the thickness of the extension 2c, the shock absorption characteristics required for the propeller shaft can be easily adjusted. Alternatively, even if the caulking force is constant, the shock absorbing characteristics of the propeller shaft can be easily adjusted by adjusting the press-fit state of the spline fitting portion 10.

The above-described embodiment has been described with reference to a form in which the invention is applied to a vehicle having a crushable body. However, the present invention is not limited to this. The present invention may be applied to any type of vehicle as long as the impact load is transmitted to the vehicle.

[0031]

According to the first aspect of the invention, since the amount of deformation of the vehicle body at the time of collision is not hindered by the contraction of the propeller shaft, the impact load at the time of collision can be sufficiently absorbed by the deformation of the vehicle body. In addition, since the yoke member moves within the hollow shaft, the propeller shaft does not bend, and secondary problems such as breakage of the fuel tank and protrusion into the cabin can be prevented, thereby improving safety. Furthermore, since the position of the yoke member is stabilized by holding the tip of the other end side of the yoke member by being covered with the swaging of the extension portion of the sleeve, the variation in the plastic deformation of the swaged portion due to the movement of the yoke member is reduced. As a result, the shock absorption characteristics of the propeller shaft are stabilized, and the impact applied to the occupant is reliably suppressed, thereby improving safety. In addition, the impact load on the propeller shaft is also absorbed by the spline fitting part with the movement of the yoke member, so the impact absorption rate by the propeller shaft is improved, the amount of shrinkage of the propeller shaft can be reduced, and the cost is reduced. While improving safety.

According to the second aspect of the present invention, even if an impact load applied to the propeller shaft is input from any of the input and output directions of the hollow shaft portion, if the impact load exceeds the holding force of the caulking portion of the extension portion. Since the yoke member held at a stable position moves in the load direction while plastically deforming the swaged portion, the shock absorbing characteristics of the propeller shaft are further improved, and safety is further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a shock absorbing unit of a propeller shaft according to one embodiment of the present invention.

FIG. 2 is an overall view showing one embodiment of a propeller shaft provided with a shock absorbing means.

FIG. 3 is an enlarged perspective view showing one embodiment of a sleeve and an intermediate member used in the present invention.

FIG. 4 is a diagram illustrating a process of assembling a propeller shaft.

FIG. 5 is an overall view showing a contracted state of a propeller shaft when receiving an impact load.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Yoke member 1a One end 1b Other end 1f, 3 The other end 2 Sleeve part 2c Extension part 4 Hollow shaft part 4a, 4b Both ends 13 Driven member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Onoda 4-2-1-1, Shimomaruko, Ota-ku, Tokyo / Mitsubishi Automotive Engineering Co., Ltd. (72) Inventor Etsuo Furuhashi 4-2-1-1, Shimomaruko, Ota-ku, Tokyo・ Mitsubishi Automotive Engineering Co., Ltd. (72) Inventor Masaki Goto 5-33-8 Shiba, Minato-ku, Tokyo ・ Mitsubishi Motors Industry Co., Ltd. (72) Inventor Kentaro Kinoshita Minami Shibatacho, Tokai City, Aichi Prefecture 266- 21 ・ Kyoei Iron Works Co., Ltd.

Claims (2)

[Claims] 1. A propeller shaft for connecting a drive source and a driven member, a yoke member having one end connected to the drive source or the driven member, and one spline fitting to the other end side of the yoke member. The other end has an extension that extends in the same direction as the insertion direction of the yoke member, and the other end of the yoke member is caulked at this extension portion at the other end of the yoke member. A propeller shaft, comprising: a holding sleeve portion; and a hollow shaft portion attached to the sleeve portion such that the caulking portion is located inside. 2. The propeller shaft according to claim 1, wherein said sleeve portion is provided at both ends of said hollow shaft portion located in the input / output direction.